1. Field of the Invention
The present invention relates generally to improvements in mobile telephone networks' Multimedia Message Service (MMS) offerings. More specifically, the present invention is related to systems and methods that support the definition, management, and application of configurable pre-transcoding operations as they relate to MMS.
2. Background of the Invention
In North America, and many other parts of the world, mobile telecommunication networks are characterized by different standards such as TDMA, CDMA, GSM, iDEN and many variants thereof, such as 2G (Second Generation Networks) and 3G (Third Generation Networks). The standards typically specify the radio interface characteristics, equipment details and associated number schemes, applicable communication protocols including the associated message definitions and characteristics of inter-connecting networks. While some of the concepts are common among these disparate standards, the commonality of the concepts is not sufficient to make devices belonging to one network talk to devices belonging to another network for wireless messaging needs.
A telecommunication network supports many services. Primary among them are voice calls and messaging. Aspects of the present invention primarily concern messaging and, therefore, this description concentrates on expanding upon the state of messaging standards.
The wireless messaging revolution started primarily with the GSM standard with the introduction of Short Message Service (SMS). An SMS message can have a maximum of 160 characters (140 octets) and is used for a number of applications including person to person messaging, binary content such as ring tones, person to application messaging and a number of other uses. Almost all other standards such as ANSI TDMA and CDMA wireless networks also have implemented an equivalent form of short message support within their networks.
There are other forms of messaging such as EMAIL, WAP and, more recently, Multimedia messages (MMS). In some cases, one form of messaging is carried over the bearers of other forms of messaging. For example, an EMAIL message could be implemented with SMS as a bearer service.
In general, it is not easily possible to exchange messages across different networks supporting different wireless standards. SMS messaging has become very popular in Europe and other parts of the world due to implementation of the GSM standard in many networks, which makes it possible to exchange SMS messages easily across the networks. In the case of ANSI TIA/EIA 41 standards, such an exchange has not been possible until aspects of the present invention were put in place in North America in the year 2001.
The exchange of messages across different networks is further complicated by roaming, number portability, quality of service, “spam”, and billing requirements. Due to its very nature, mobile networks permit roaming of subscriber units within the network and other networks implementing compatible standards, provided a business arrangement between the effected networks exists. In order to deliver a message to a mobile unit, it is necessary to find its current location and associated gateway and interface address.
One of the features of number portability is the ability to port a number from one service provider to another. Number portability poses problems with the delivery of messages when relatively static routing tables are used. A similar but independent problem arises out of “number range contamination”. In North America, for example, messages and calls are routed to networks using what is known as NPA/NXX ranges. This methodology refers to routing of calls using the first 6 digits of the telephone number (TN) in the North American Number Plan (NANP). Traditionally, a set of number ranges segmented by NPA/NXX are assigned to service providers.
Recently, in the United States, a change has been made in telephone number range assignments to service providers. Instead of the usual 6 digit number ranges, the assignments are made, now, using 7 digit ranges. However, during the reassignment, certain numbers in a range may be, what is termed as, “contaminated,” where a small percentage of numbers may belong to one service provider, even though the range as a whole is owned by another service provider.
In addition to the contaminated and ported number issues mentioned above, there are a number of other inter-connectivity issues that may need to be addressed for flexible and reliable message bridging across different networks. For example, a source and destination network (with respect to a message going between subscribers of those two networks) may be inter-connected by more than one Intermediate network. The routing tables and associated methodologies must account for this multi-hop connection. A destination network may be accessible only through a designated service provider to the network. For example, a SS7 service provider may have exclusive access to a carrier's network and the message must be routed through such a connection. There may be multiple types of connections to a network to reach the same mobile subscriber. Further, there may be multiple instances of a particular type of connection to a network to reach the same mobile subscribers.
In addition, there might be varying levels of Quality of Service for multiple connections to the same network.
To summarize, the following are many of the challenges that need to be addressed for successful and reliable message exchange between disparate wireless networks:                Protocol Conversion—ability to account for protocol differences        Transmission network support—ability to connect with the right kind of transmission network        Inter-Domain or Inter-network Addressing Conversion—ability to perform address translation, as necessary        Dynamic Routing Lookup—ability to resolve for accurate and timely routing information        Message Transformation—ability to transform messages based on business and technical needs        Storage and re-transmittal—ability to store and forward based on business and technical needs        Recording of transmission events for billing and other uses—ability to record the message transmission events        Management channel support—ability to manage message transmission        Anti-spam, Authentication and other centralized value add services—ability to provide network protection.        Lateral transmission to other Intermediary networks—ability to interface with multiple networks        Transaction support—ability to reliably transact a message delivery attempt        Quality of Service—ability to support varying quality levels in providing service        
As previously mentioned, MMS is a follow-on to the wildly-successful Short Message Service (SMS) or ‘text messaging’ communication channel. As an initial point of reference, the WebOpedia on-line technical dictionary defines MMS as:                a store-and-forward method of transmitting graphics, video clips, sound files and short text messages over wireless networks using the WAP protocol. Carriers deploy special servers, dubbed MMS Centers (MMSCs) to implement the offerings on their systems. MMS also supports e-mail addressing, so the device can send e-mails directly to an e-mail address. The most common use of MMS is for communication between mobile phones.        
As MMS services have emerged, so too have a plurality of MMSC vendors (e.g., LogicaCMG, OpenWave, Nokia, among others). While, in general, each MMSC vendor strives to develop its platform to a set of publicly-available definitional standards, vendor-specific implementation nuances or differences inevitably arise. Those nuances or differences (relating to, as an example, specific messaging protocol support) are then magnified by each wireless carrier's own unique implementation of a vendor's MMSC platform within a carrier's network (involving, as an example, acceptable message size, image type, etc.). These factors, in the end, yield a significant inter-carrier or cross-carrier interoperability challenge.